Obama Rallies Troops in Afghanistan: 'Tired of Playing Defense'

President Barack Obama reaches for a Purple Heart medal which he presented to a wounded soldier at Bagram Air Field in Afghanistan, Dec. 3, 2010. The President presented five Purple Hearts to soldiers during his overnight trip to Afghanistan.

One year and two days after President Obama appeared before an audience at West Point and told the nation he was sending 30,000 more U.S. troops to Afghanistan, he has come to meet with troops in the war-torn country for his second visit as commander in chief. He was greeted by bad weather and storms of an altogether different kind.

The rough winds and dark clouds could symbolize the challenges the president and his team face here as the war -- now in its 10th year -- risks being undermined by a corrupt government, a strong insurgency, leaks of classified cables, waning public support and shifting political winds.

In a pep talk to troops at the Bagram Air Base, Obama praised their work and expressed cautious optimism about the future.

"You are protecting your country. You are achieving your objective. You will succeed in your mission," a casually dressed Obama said to 3,850 troops in the audience. "We said we were going to break the Taliban's momentum, and that's what you're doing. You're going on the offense, tired of playing defense."

The president was originally scheduled to have a "working dinner" with Afghan President Hamid Karzai at his presidential palace in Kabul in this unannounced visit and to meet with civilian personnel at the, U.S. Embassy in the capital city.

Obama's arrival in Afghanistan was first reported by ABC News' Martha Raddatz, who learned of Obama's arrival independently while on assignment in Afghanistan and was not traveling with the White House press pool.

There are more than 1,000 U.S. government civilian employees here, from the State Department, USAID and nine other agencies, a tripling since the president announced his new policy one year ago.

But strong winds and low cloud cover made helicopter travel hazardous, so in the last few hours of the president's trip to Bagram on Air Force One, the Kabul part of the visit was scrapped.

The "ceiling" -- the cloud cover -- between Bagram and Kabul is less than 1,000 feet, White House press secretary Robert Gibbs told reporters on Air Force One. Wind speeds are 45 mph and above, with less than two miles of visibility.

"It all made helicopter travel not an option," Gibbs said.

Instead, the president spoke over the phone with Karzai for 15 minutes, before meeting with Gen. David Petraeus, Ambassador Karl Eikenberry, National Security Adviser Tom Donilon and Gen. Douglas Lute.

Deputy National Security Adviser for Strategic Communications, Ben Rhodes, said the cancellation of the visit to the palace wasn't of tremendous importance, because the president and Karzai spoke at a NATO summit in Lisbon, Portugal, a few weeks ago, after Karzai expressed frustration with night raids by ISAF forces and Obama said Karzai has "got to listen to us as well."

The president today met with eight wounded patients at Bagram -- five troops and three civilians -- and presented four Purple Heart awards. He also met with troops from the 101st Airborne Division, which is in the midst of its fourth combat deployment since 2003, having served two tours in Iraq and one previous 15 month rotation in Afghanistan from 2008 through 2009.